A basic cheap auto motion alarm could be hooked up. It might not have an infinite lifespan. Amazon has a marinized alarm for about $100. For more money there are models which are GPS enabled and will phone home if activated.

The quickest, easiest sliding window lock is a short piece of dowel that just fits in the aluminium "groove" that the window slides along.
It stops the window from moving more than half an inch when the "stick" is cut to the right length.

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